Effect of Biocides - Edta Combinations against Biofilm Forming Organisms in Catheter - Associated Urinary Tract Infections

Catheter associated urinary tract infection (CA-UTI) is one of the most common hospital-acquired infection. Prolong use of urinary catheter increases the risk of CA-UTI because of biofilm forming organisms. Biofilm developed on catheter protects the organism from host defences and antimicrobial substances which makes CA-UTI difficult to treat. Biofilms show enhanced virulence due to resistance to biocides, antibiotics and hence they are difficult to eradicate from the surface. Biocides are chemical compounds with antimicrobial properties. Dettol, Chlorhexidine and 70% Ethanol are commonly used biocides to disinfect catheters. EDTA, a well-known chelating agent which chelates metal ions necessary for quorum sensing, prevents biofilm formation. Due to increasing use of biocides, microorganisms are developing resistance to biocides. The present study is aimed to explore the effect of 17% EDTA in combination with Dettol, Chlorhexidine and 70% Ethanol on the common biofilm forming catheter associated bacteria, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae. The addition of 17% EDTA was found to significantly increase the efficacy of all the studied biocides against all the four potentially biofilm forming organisms. This study hereby recommends the use of biocides-EDTA combinations, rather than the biocides alone, in combating the catheter-associated UTI.